problem 1: In the ray tracing, ambient, diffuse and Phong's specular shading can be employed to define the color at a point on a surface. Describe what each of the three terms refers to and what real affect each is trying to model.
problem 2: The diagram shown below represents a scene being ray traced. The circles might be taken to represent the cross-sections of spheres.
A particular ray from the eye-point O has been found to have its closest intersection with the object at point P. Show, on a diagram, all consequent rays and vectors which should be found in order to compute the shading at point P. Describe the purpose of each one.
a) Each object has ambient, diffuse and specular reflections; however is not a perfect reflector.
b) Each object is opaque.
c) All rays and vectors lie in the plane of paper.
d) We are not employing distributed ray tracing.
problem 3: Suppose now that all of the objects are perfect reflectors (in addition to having ambient, diffuse and specular reflection). Show, on a diagram, the additional rays that require to be computed and describe the purpose of each one.